The 35-year-old said changes to his putting game helped.

"I've changed a little bit of my left-hand grip, but the biggest change is my putter got lengthened," he said.

"My coach has been wanting me to do this for over a year and I just didn't feel comfortable, but finally I wised up and listened to him.

"My strike is much more solid now. It was getting out of hand. I was starting to lose some confidence."

Bohn has one PGA Tour victory, the B.C. Open in 2005, but is best known for winning $1 million in 1992 at a hole-in-one competition in Alabama.

He was a college player at the time, but the annual $50,000 installments allowed him to pursue his professional aspirations.

"It was a life changing experience. In all honesty, it is the only reason I'm sitting here today," he added.

Adam Scott, winner of last week's Byron Nelson Championship, just made the cut, sinking a 14-footer at the last to advance to the final two rounds, 10 shots off the pace.

However, Masters champion Trevor Immelman made an early exit for the second week in a row.